Hi,
The speed difference is 10 miles / hr. The difference in gust factor is 1.7 sec.
1.7 sec = 1.7/3600 [hr] = 0.000472 [hr]. In 1.7 sec at 130 miles/ hr the slow car will go 130*0.000472 = 0.0614 miles. It will take 0.0614/10 = 0.00614 [hr] or 22.1 seconds untill the fast car will get the slow car and from now it it will lead.
Best regards,